![]() Artistical representation of a super-Neptune exoplanet. | |
Discovery[1][2] | |
---|---|
Discovered by | Dedrick et al. |
Discovery date | 2020 |
Radial velocity | |
Designations | |
HD 97101 Ac, HIP 54646 c[3] | |
Orbital characteristics | |
1.4+0.055 −0.06 AU[2] | |
Eccentricity | 0.093+0.1 −0.064[2] |
749.83+4.35 −3.63 d[2] 2.054 year | |
74°+74° −200°[2] | |
Star | Gliese 414 A |
Physical characteristics | |
8.4+3.6 −2.5 R🜨 (0.749+0.321 −0.223 RJ)[2] | |
Mass | 53.83+9.18 −8.58 M🜨 (0.169+0.029 −0.027 MJ)[2] |
Temperature | 123.3±13.2 K (−149.7 °C (−237.5 °F))[2][a] |
Gliese 414 Ac, or GJ 414 Ac, is an exoplanet orbiting Gliese 414 A, a K-type main-sequence star located 39 light-years from Earth, in the constellation Ursa Major.[4][note 1] It is classified as a super-Neptune exoplanet, being at least 54 times more massive than the Earth and about 8.5 times larger.[2] Gliese 414 Ac orbits its parent star at a distance of 1.4 astronomical units and completes one revolution around it every 2 years and 20 days.[2] It is one of the two planets orbiting Gliese 414 A, the another is Gliese 414 Ab, a sub-Neptune.[3]
Characteristics
[edit]Gliese 414 Ac is classified as a super-Neptune (or sub-Saturn),[2][3] a type of exoplanets that are more massive than Neptune, but less massive than Saturn, having masses between 20 and 80 ME.[5] The planet has a minimum mass of 54 ME and a radius of 8.4 R🜨,[2] both values between Neptune and Saturn.[b]
It completes one orbit around its star approximately every two years, and is located at a distance of 1.4 astronomical units (210,000,000 km) from it, too far to be located in the habitable zone of its star, which extends up to 0.7 AU.[2] Due to the great separation from its star, the planet is frigid, having an equilibrium temperature of around -150 °C,[2] comparable to Saturn, which has a temperature of -140 °C.[7] Gliese 414 Ac is as a potential candidate for future direct imaging missions.[2][3][8]
Discovery
[edit]Gliese 414 Ac was discovered in 2020 by analyzing radial velocity data from Keck's HIRES instrument and the Automated Planet Finder at Lick Observatory, as well as photometric data from KELT.[3]
Host star
[edit]Gliese 414 Ac orbits Gliese 414 A, an orange dwarf (spectral type K7V[9]) that is smaller and cooler than the Sun. The star has a radius of 0.68 R☉, a mass of 0.65 M☉ and a temperature of 4,120 K (3,850 °C).[2] It is a binary star, having an orbital companion called Gliese 414 B, a red dwarf star that is at a projected distance of 408 astronomical units from it.[3][8]
The stellar system is located about 39 light-years from the Earth, in the constellation Ursa Major.[10][note 1] Both stars are too faint and can't be seen with the naked eye.[10]
There is another planet orbiting Gliese 414 A. Named Gliese 414 Ab, it is a sub-Neptune that is located 0.23 AU (34,000,000 km) from it (6 times closer than Gliese 414 Ac).[2] The planet has an eccentric orbit and its distance from its star varies between 0.13 and 0.34 AU, which means that it is occasionally located in the optimistic habitable zone.[2] The planet has a radius of 2.95 R🜨 and a minimum mass of 7.6 ME.[2]
See also
[edit]- List of coolest exoplanets
- Super-Neptune
- Ursa Major
- Gliese 414
- List of star systems within 35-40 light years
Notes and references
[edit]- ^ Martin, Pierre-Yves (2020). "Planet GJ 414 A b". Extrasolar Planets Encyclopaedia. Archived from the original on 2023-12-14. Retrieved 2023-12-14.
- ^ a b c d e f g h i j k l m n o p q r s Dedrick, Cayla M.; Fulton, Benjamin J.; Knutson, Heather A.; Howard, Andrew W.; Beatty, Thomas G.; Cargile, Phillip A.; Gaudi, B. Scott; Hirsch, Lea A.; Kuhn, Rudolf B.; Lund, Michael B.; James, David J.; Kosiarek, Molly R.; Pepper, Joshua; Petigura, Erik A.; Rodriguez, Joseph E. (2021-02-01). "Two Planets Straddling the Habitable Zone of The Nearby K Dwarf Gl 414A". The Astronomical Journal. 161 (2): 86. arXiv:2009.06503. Bibcode:2021AJ....161...86D. doi:10.3847/1538-3881/abd0ef. ISSN 0004-6256.
- ^ a b c d e f "Open Exoplanet Catalogue - Gliese 414 Ab". www.openexoplanetcatalogue.com. Archived from the original on 2023-12-14. Retrieved 2023-12-14.
- ^ "Gliese 414 | NASA Exoplanet Archive". exoplanetarchive.ipac.caltech.edu. Archived from the original on 2023-12-09. Retrieved 2023-12-14.
- ^ Staff, Space.com (2009-03-14). "Super-Neptune Planet Found". Space.com. Archived from the original on 2024-01-31. Retrieved 2024-01-31.
- ^ "Planetary Physical Parameters". ssd.jpl.nasa.gov. Archived from the original on October 4, 2022. Retrieved January 31, 2024.
- ^ "Solar System Temperatures - NASA Science". science.nasa.gov. Archived from the original on 2023-10-01. Retrieved 2023-12-14.
- ^ a b Anderson, Natali (2020-09-21). "Astronomers Find Two Massive Exoplanets in Nearby Binary System | Astronomy | Sci-News.com". Sci.News: Breaking Science News. Archived from the original on 2024-01-13. Retrieved 2024-01-13.
- ^ a b "HD 97101". SIMBAD. Retrieved January 31, 2024.
- ^ a b "Gliese 414". Stellar Catalog. Archived from the original on December 13, 2023. Retrieved January 31, 2024.
- ^ Assuming a bond albedo of 0.343, the same as Saturn.
- ^ Neptune has a mass of 17.15 ME and a radius of 3.88 R🜨, while Saturn has a mass of 95.2 ME and a radius of 9.45 R🜨.[6]